通过PHP访问网址的最快方式

Question

在没有任何输出的情况下使用PHP访问URL的最快方法是什么？

我使用file_get_contents和CURL对下面的代码进行了测试，但结果不稳定且非常接近。

function abtest()
{
    $arr_to_return = array();
    $t = microtime(true);
    file_get_contents('http://127.0.0.1/test.html');
    $e = microtime(true);
    $arr_to_return['file_get_contents'] = $e-$t;

    $t = microtime(true);
    $handle = curl_init('http://127.0.0.1/test.html');
    curl_setopt($handle, CURLOPT_NOBODY, TRUE);
    curl_exec($handle);
    curl_close($handle);
    $e = microtime(true);

    $arr_to_return['curl'] = $e-$t;

    return $arr_to_return;
}

$limit = 20;
$count = 0;
$result = array();
$filegetcontents = 0;
$curl = 0;
do{
    $test = abtest();
    $result['file_get_contents'][] = $test['file_get_contents'];
    $filegetcontents += $test['file_get_contents'];
    $result['curl'][] = $test['curl'];
    $curl += $test['curl'];
    $count++;
} while ( $count < $limit);

echo '<pre>';
print_r($result);
echo '</pre>';

echo 'Average: file_get_contents ('.($filegetcontents/$limit).') curl ('.($curl/$limit).')';

根据建议，我将它放入一个函数中，并在localhost上使用直接IP循环20次。

结果如下：

Array
(
    [file_get_contents] => Array
        (
            [0] => 0.0055451393127441
            [1] => 0.0056819915771484
            [2] => 0.0056838989257812
            [3] => 0.014945983886719
            [4] => 0.014636993408203
            [5] => 0.014842987060547
            [6] => 0.0053179264068604
            [7] => 0.015022039413452
            [8] => 0.014861106872559
            [9] => 0.015033960342407
            [10] => 0.015429973602295
            [11] => 0.015249013900757
            [12] => 0.01471996307373
            [13] => 0.015311002731323
            [14] => 0.0054020881652832
            [15] => 0.015032052993774
            [16] => 0.0051870346069336
            [17] => 0.014680147171021
            [18] => 0.014776945114136
            [19] => 0.015046119689941
        )

    [curl] => Array
        (
            [0] => 0.0013649463653564
            [1] => 0.0017318725585938
            [2] => 0.0013041496276855
            [3] => 0.0013928413391113
            [4] => 0.0013279914855957
            [5] => 0.0013871192932129
            [6] => 0.011061906814575
            [7] => 0.0013771057128906
            [8] => 0.010823011398315
            [9] => 0.0015439987182617
            [10] => 0.0015928745269775
            [11] => 0.0014979839324951
            [12] => 0.0016429424285889
            [13] => 0.011864900588989
            [14] => 0.0015189647674561
            [15] => 0.0014710426330566
            [16] => 0.0014939308166504
            [17] => 0.001460075378418
            [18] => 0.011038064956665
            [19] => 0.010931015014648
        )

)

Average: file_get_contents (0.012120318412781) curl (0.0038913369178772)

在大多数情况下，似乎CURL的结果优于file_get_contents。除了上面以外，还有更快的方法吗？